View Full Version : 870 mag tube indents (express)

March 28, 2006, 02:30 PM
what is the best way of getting rid of thoes troublesom dents im trying to add a pistol grip wich went fine along with a tac light wich missing parts are on order and a 10 shot mag extention it all looked beautiful untill i tried loading it damn indents. i dont want to drill it and id hate to mess up the bluing by whailing on it i see this is a big problem with express models ay and every idia would be great thanks

March 28, 2006, 03:12 PM


March 28, 2006, 03:19 PM
The basic techniques of getting rid of the "dimples" are:

Drill them out with a 1/4" drill, then polish the inside of the tube to make sure all traces are gone.
The holes are completely covered by the barrel's support ring when the gun is assembled.

One poster uses an appropriate socket from a socket wrench set as a "ironing" tool to press the lugs out, then polishes inside.
Once you have the dimples pressed out, you can use a small steel hammer to gently tap the dimples flush by inserting the socket into the tube as a support.

Grind them out with a Dremel or flex-shaft and abrasive tips.

Have a gunsmith use a shotgun hydraulic dent remover tool to press them out.

And variations on the above methods.

Whatever you use, you MUST be 100% sure to polish all traces of the dimples or any remaining burrs out, or the follower or shells will hang up in the tube, causing a stoppage.

March 28, 2006, 08:33 PM
But after the dimples are removed there is nothing to keep the barrel retaining ring from coming loose.

March 28, 2006, 10:12 PM
Good point. Unless your barrel has a detent ball and your mag cap is the correct style, you'll have a devil of a time keeping that barrel tight. I have done this mod on a few Express guns but I also swapped them over to older rifle-sighted barrels w/detents and the cap to match.
That Express system is a drag if you want an extension but it does secure the barrel.

March 29, 2006, 01:10 AM
As long as the poster is going to use his extension, the extension barrel clamp will prevent the extension from unscrewing.

Going back to a standard magazine with a cap is another story.

March 29, 2006, 01:21 PM
hey due to the fact that my wife would kill me if i spent another dime on anything gun related i drilled out the dents with a 1/8 in drill bit then ground out the remaining burs left with my dremel (the best tool on earth) then buffed it with the dremel so the plug would slide through freely i was woried about the holes weakening the barel but i guess if i hit it on anything that hard id dent the tube anyway also the ring on the barrel covers the holes

thanks for the help

ranger dave
March 31, 2006, 11:44 AM
i took a socket just smaller then the tube and hit it with a rubber hammer flatened them right out no mus no fus

April 1, 2006, 08:19 AM
Just for spreading the information, the brand new 20 gauge still do not have dimples at all. Don't know why they picked on the 12 but I hope they change that practice.

April 2, 2006, 10:35 AM
i took a socket just smaller then the tube and hit it with a rubber hammer flatened them right out no mus no fus

That must be a whale of a rubber hammer! I needed a ballpeen to hammer mine out. They were quite tough.

April 4, 2006, 02:54 PM
also what brand and size socket because i tried mine and it didnt get them all the way out